The user of a wireless communication terminal provided with a plurality of wireless systems can select a wireless system suitable for various situations and can use the selected wireless system. Therefore, user convenience is improved. In addition, communication network operators can distribute a data communication load to various wireless systems, which promotes the construction of multi-wireless systems in terminals or PCs.
In order to improve user convenience, the following method is generally used: a plurality of multi-wireless systems are not manually selected and used, but a plurality of wireless systems are constantly turned on and are automatically switched. For the switching of wireless connections, a wireless system different from the wireless system which is currently used for communication is periodically searched for and a connection thereto is checked. A search method varies depending on the service coverage of each wireless system.
For example, a cellular network, such as a long term evolution (LTE) network, has a wide support range and a wireless local area network (LAN) system, such as a wireless fidelity (Wi-Fi (registered trademark)) system, has a narrow support range. Therefore, the wireless communication terminal normally performs communication with the cellular network. When a wireless LAN is detected, the wireless communication terminal performs a control process of switching the communication network from the cellular network to the wireless LAN even though communication is continuously performed using the cellular network.
For example, the advantage of communication using the wireless LAN is that there is no charge for communication packets or the user can benefit from high-speed communication with a data transmission rate greater than 100 Mbps. Telecommunications carriers make a policy of performing communication using the wireless LAN as much as possible when traffic congestion occurs in the cellular network.
The disadvantage of communication using the wireless LAN is that there is a large variation in communication quality and only low-speed communication is performed depending on the degree of congestion or the communication band of the backbone of the access point. When the wireless communication terminal is in this state, the user manually switches the wireless LAN connection to the cellular network or continuously uses a weak wireless LAN until communication is disconnected.
In recent years, a simultaneous communication method which uses the cellular network and the wireless LAN at the same time has been used. This method constantly monitors the two wireless systems. Therefore, it is possible to perform control such that the wireless system with higher communication quality is used as much as possible.
Patent Document 1: Japanese Laid-open Patent Publication No. 2008-136150
Patent Document 2: Japanese Laid-open Patent Publication No. 2011-166251
However, in the simultaneous communication method, in some cases, an application installed in the wireless communication terminal performs an unintended operation. For example, some of the applications installed in the wireless communication terminal recognize whether the wireless communication terminal is connected to the wireless LAN or the cellular network and determine the operation mode on the basis of the recognition result.
For example, there is a preload function in which a browser application reads a linked site from a site first in order to display content at high speed. When the preload function is performed, a large amount of data is transmitted. Therefore, the browser application performs the preload function only when the wireless LAN is used, considering a communication charge.
However, when the simultaneous communication function is performed, it is difficult for the browser application to specify the wireless system for communication. Therefore, in some cases, the browser application performs the preload function, with the wireless communication terminal connected to the cellular network, which results in an unintended charge. As such, in the simultaneous communication method, in some cases, the application installed in the wireless communication terminal performs an unintended operation, which creates a disadvantage for the user.